The invention relates to a lamp/reflector unit comprising
a concave reflector with an axis, which has near its top a neck-shaped portion around that axis, PA0 an electric lamp provided with PA0 a metal centring member in the neck-shaped portion having a transverse wall cross to the axis of the reflector, which wall has an opening in which the seal is accommodated,
a lamp vessel having a seal, PA1 an electric element in the lamp vessel, PA1 current supply conductors extending from the electric element through the seal to the exterior,
the lamp vessel being secured in the neck-shaped portion by means of cement.
Such lamp/reflector units are commercially available.
The centring member--a flat metal plate, a metal plate having a cylindrical rim, or a metal bush--facilitates assembly of the lamp in the reflector in a pre-determined position of the electric element relative to the reflector owing to the fact that the member centres the seal in the neck-shaped portion. By shifting and/or tilting the lamp vessel, it is possible to bring the electric element in the correct position. The centring member also has for its object to prevent the cement from flowing from the neck-shaped portion before it has set and from being deposited on the reflector.
It has been shown that fractures of the lamp vessels frequently occur in these lamp/reflector units. The seal of the lamp vessel breaks in the spot where that seal emerges from the centring member.